Spur attached by insertion into the heel of a riding boot



FIG. 1 is a side view of a spur attached by insertion into the heel of a riding boot shown by dashed lines, showing my new design, the opposite side being a mirror image thereof;

FIG. 2 is a top plan view thereof;

FIG. 3 is a bottom view thereof;

FIG. 4 is a left end view thereof; and,

FIG. 5 is a right end view thereof.

The broken line showing of a riding boot heel in FIG. 1 is for illustrative purposes only and forms no part of the claimed design. 

The ornamental design for a spur attached by insertion into the heel of a riding boot, as shown and described. 